I have sealed around the penetrations for the AC lines. I sealed from the inside and outside and used a bright light to make sure I didn't miss anything since I don't want CO coming through those holes.I used a small piece of the wing root gap weatherstrip.
Unrelated - make double sure the penetrations through the fuselage for the condenser refrigerant lines are completely sealed. Otherwise, you may get some CO infiltration into the cabin. I know of three local RV-10’s with air conditioning that had this issue. It was resolved by sealing those penetrations with grommets and RTV.
I would like to seal up everywhere I can within reason. What did you do to seal up around the wing spar area?i also used an outer backer matched to skin shape and used epoxy flox on the inside to make a base. Then some filler and sand to shape. Will never know it was there after paint. Don't leave it open, as it will force a lot of air movement in the cabin, assuming you are going to be sealing up other openings where the wing spar enters the fuse.
aileron tube covers and a combo of foam and rtv, mostly rtv, at the gaps around the spar and other poorly sealed openings. If i could see light through it, i sealed it. It pays off, as I have almost 0 air movement in the cabin. No drafts of any kind and I didn't even need stick boots.Those are some good ideas, thanks.
I would like to seal up everywhere I can within reason. What did you do to seal up around the wing spar area?